Compliant cutting die apparatus for cutting fuel cell material layers

ABSTRACT

A cutting apparatus for use with a platen die station is employed for cutting relatively thin planar material layers, such as thin material layers used in the construction of fuel cells. The cutting apparatus includes a die having a substantially planar first surface and a substantially planar second surface. A cutting surface and at least one bearer surface respectively protrude from the first surface of the die. A height of the bearer surface is substantially equal to a height of the cutting surface, such that the bearer surface prevents damage to the cutting surface when the cutting surface and bearer surface are moved to contact an anvil surface of the platen die station. One or more layers of a compliant material, such as polyethylene or polypropylene, may be situated in contact with the second surface of the die to add compliance to the cutting apparatus.

FIELD OF THE INVENTION

[0001] The present invention relates generally to cutting dies and, moreparticularly, to a cutting die and cutting station for use in cuttingrelatively thin material layers, such as material layers of a fuel cell.

BACKGROUND OF THE INVENTION

[0002] Various types of cutting dies have been developed to cut andperforate a wide variety of materials. One type of cutting die apparatusis referred to as a rotary cutting die. Rotary dies are typicallymounted onto magnetic steel rolls. These steel rolls provide anextremely rigid support for the die. A rotary die cuts against a steelanvil roll.

[0003] Another type of cutting die apparatus is referred to as a platenstyle die. A platen die station incorporates a cutting die and an anvilwhich are brought into contact axially under force. Both platen androtary die stations are useful in many applications. However,limitations inherent in conventional rotary and platen die apparatusesrender these cutting devices less than optimal when cutting relativelythin layers of material, such as materials having a thickness of about0.001 inches.

[0004] There is a need for an improved cutting apparatus which is wellsuited for cutting relatively thin layers of material, such as materialsused in the construction of fuel cells. There is a further need for animproved cutting apparatus that exploits beneficial attributes of bothrotary and platen style die apparatuses. The present invention fulfillsthese and other needs.

SUMMARY OF THE INVENTION

[0005] The present invention is directed to a cutting apparatus for usewith a platen die station for cutting relatively thin planar materiallayers. The cutting apparatus of the present invention is particularlywell suited for cutting thin material layers used in the construction offuel cells. According to one embodiment, the cutting apparatus includesa die having a substantially planar first surface and a substantiallyplanar second surface. A cutting surface protrudes from the firstsurface of the die.

[0006] The cutting apparatus further includes at least one bearersurface that protrudes from the first surface of the die. A height ofthe bearer surface is substantially equal to a height of the cuttingsurface, such that the bearer surface prevents damage to the cuttingsurface when the cutting surface and bearer surface are moved to contactan anvil surface of the platen die station. One or more layers of acompliant material, such as polyethylene or polypropylene, may besituated in contact with the second surface of the die to add complianceto the cutting apparatus.

[0007] In accordance with another embodiment, a platen die assemblyincorporates a cutting apparatus for cutting relatively thin planarmaterial layers. The plate die assembly includes a first plate and asecond plate. The second plate includes an anvil surface. The firstplate and second plate are arranged to permit relative movementtherebetween.

[0008] A die of the platen die assembly includes a substantially planarfirst surface and a substantially planar second surface. The secondsurface of the die is affixed to the first plate. A cutting surfaceprotrudes from the first surface of the die. At least one bearer surfaceprotrudes from the first surface of the die. A height of the bearersurface is substantially equal to a height of the cutting surface.

[0009] A controllable actuator effects contact between the first andsecond plates. The bearer surface prevents damage to the cutting surfacewhen the cutting surface and bearer surface are moved to contact theanvil surface of the second plate under pressure. One or more layers ofa compliant material may be situated between the second surface of thedie and the first plate to add compliance to the cutting apparatus.

[0010] The above summary of the present invention is not intended todescribe each embodiment or every implementation of the presentinvention. Advantages and attainments, together with a more completeunderstanding of the invention, will become apparent and appreciated byreferring to the following detailed description and claims taken inconjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011]FIG. 1 is an illustration of a fuel cell and its constituentlayers;

[0012]FIG. 2 is an illustration of a cutting die employing cutting andbearer stop features in accordance with an embodiment of the presentinvention;

[0013]FIG. 3 is another view of the cutting die shown in FIG. 2; and

[0014]FIG. 4 is an illustration of a cutting die station employing acutting die having cutting and bearer stop features in accordance withan embodiment of the present invention.

[0015] While the invention is amenable to various modifications andalternative forms, specifics thereof have been shown by way of examplein the drawings and will be described in detail. It is to be understood,however, that the intention is not to limit the invention to theparticular embodiments described. On the contrary, the intention is tocover all modifications, equivalents, and alternatives falling withinthe scope of the invention as defined by the appended claims.

DETAILED DESCRIPTION OF VARIOUS EMBODIMENTS

[0016] In the following description of the illustrated embodiments,reference is made to the accompanying drawings which form a part hereof,and in which is shown by way of illustration, various embodiments inwhich the invention may be practiced. It is to be understood that theembodiments may be utilized and structural changes may be made withoutdeparting from the scope of the present invention.

[0017] A cutting die apparatus of the present invention can be employedto cut relatively thin material layers. For example, a cutting dieapparatus of the present invention is well suited for cutting layers ofmaterials used in the construction of fuel cell. The material layersused to construct a fuel cell can have a thickness of about 0.001inches. Such materials can have varying porosity and can vary in termsof brittleness. One skilled in the art will readily appreciate thataccurately and safely cutting thin materials, such as those used in fuelcell construction, is a significant challenge.

[0018] A cutting die apparatus of the present invention effectivelyexploits several beneficial features of rotary cutting dies and adaptssuch features for use on platen presses. In addition, a cutting dieapparatus of the present invention incorporates one or more stops orbearers built into the cutting die. The built-in bearers operate tocontrol the stroke of a cutting press that employs a cutting dieapparatus of the present invention. Integration of one or more stops orbearers built into the cutting die advantageously eliminates the needfor stops arranged external of the cutting die. Such external stops areknown to be expensive and require careful adjustment by a skilledmachinist after each die change.

[0019] According to an embodiment of the present invention, the heightof the bearer or bearers of the cutting die apparatus matches the heightof the cutting surface of the cutting die apparatus. Because the heightsof the bearer and cutting surfaces are matched on the cutting die, therisk of crushing the cutting surface is significantly reduced, if noteliminated.

[0020] Conventional platen die apparatuses often employ a sacrificialsoft material, such as nylon, as a receiving surface (i.e., anvilsurface) that contacts the cutting surface of the die at the end of thepress stroke. Although this approach reduces the likelihood ofundesirable crushing of the cutting surface, the relative softness ofthe nylon receiving surface provides insufficient support and stabilitywhen attempting to cut relatively thin material layers on the order of0.001 inches in thickness.

[0021] Because the heights of the bearer and cutting surfaces arematched on the cutting die, the receiving or anvil surface of a platenpress that employs a cutting die apparatus of the present invention canbe made of hard material, such as a high strength metal suitable for useas an anvil. Integration of the bearer and cutting surfaces onto acutting die apparatus of the present invention allows for the use of ahard anvil surface, which is a beneficial feature of rotary cutting diesheretofore unavailable using conventional platen die cutting techniquesas applied to the cutting of very thin layers of material.

[0022] In accordance with another embodiment of the present invention,the cutting die apparatus can include a thin compliant material situatedbetween the non-cutting surface of the cutting die apparatus and aplaten press surface. It is well understood by those skilled in the artthat cutting thin material layers, such as fuel cell layers on the orderof 0.001 inches in thickness, using certain cutting dies can beproblematic where the cutting surface height varies along the length ofthe cutting surface. For example, the height of the cutting surface of aparticular cutting die can vary by about 0.0005 inches. This variationin cutting surface height is largely due to inaccuracies in the cuttingdie fabrication process. According to this embodiment, a small amount ofcompliance is integrated into the cutting die apparatus. By adding aslightly compliant support behind the cutting die, very thin materialscan be cleanly cut, and any slight variation in cutting die height canbe accommodated without adversely affecting the cutting process.Further, employment of a compliant material behind the cutting dieprovides for cutting of very thin materials against a hard anvilsurface.

[0023] A cutting die apparatus of the present invention can be employedto facilitate automated cutting of material layers defining a fuel cellor a portion of a fuel cell. A fuel cell is an electrochemical devicethat combines hydrogen fuel and oxygen from the air to produceelectricity, heat, and water. Fuel cells do not utilize combustion, andas such, fuel cells produce little if any hazardous effluents. Fuelcells convert hydrogen fuel and oxygen directly into electricity, andcan be operated at much higher efficiencies than internal combustionelectric generators, for example.

[0024] A typical fuel cell is depicted in FIG. 1. The fuel cell 10 shownin FIG. 1 includes a first fluid transport layer 12 adjacent an anode14. Adjacent the anode 14 is an electrolyte membrane 16. A cathode 18 issituated adjacent the electrolyte membrane 16, and a second fluidtransport layer 19 is situated adjacent the cathode 18. In operation,hydrogen fuel is introduced into the anode portion of the fuel cell 10,passing through the first fluid transport layer 12 and over the anode14. At the anode 14, the hydrogen fuel is separated into hydrogen ions(H⁺) and electrons (e⁻).

[0025] The electrolyte membrane 16 permits only the hydrogen ions orprotons to pass through the electrolyte membrane 16 to the cathodeportion of the fuel cell 10. The electrons cannot pass through theelectrolyte membrane 16 and, instead, flow through an externalelectrical circuit in the form of electric current. This current canpower an electric load 17, such as an electric motor, or be directed toan energy storage device, such as a rechargeable battery.

[0026] Oxygen flows into the cathode side of the fuel cell 10 via thesecond fluid transport layer 19. As the oxygen passes over the cathode18, oxygen, protons, and electrons combine to produce water and heat.

[0027] Individual fuel cells, such as that shown in FIG. 1, can becombined with a number of other fuel cells to form a fuel cell stack.The number of fuel cells within the stack determines the total voltageof the stack, and the surface area of each of the cells determines thetotal current. The total electrical power generated by a given fuel cellstack can be determined by multiplying the total stack voltage by totalcurrent.

[0028] A cutting die apparatus of the present invention can be employedto facilitate automated cutting of material layers in the constructionof fuel cells of varying technologies. For example, a cutting dieapparatus of the present invention can be employed to cut materiallayers used to construct proton exchange membrane (PEM) fuel cells. PEMfuel cells operate at relatively low temperatures (about 175 degreesF.), have high power density, can vary their output quickly to meetshifts in power demand, and are well suited for applications where quickstartup is required, such as in automobiles for example.

[0029] The proton exchange membrane used in a PEM fuel cell is a thinplastic sheet that allows hydrogen ions to pass through it. The membraneis coated on both sides with highly dispersed metal or metal alloyparticles (e.g., platinum or platinum/ruthenium) that are activecatalysts. The electrolyte used is typically a solid organic polymerpoly-perfluorosulfonic acid. Use of a solid electrolyte is advantageousbecause it reduces corrosion and management problems.

[0030] Hydrogen is fed to the anode side of the fuel cell where thecatalyst encourages the hydrogen ions to release electrons and becomehydrogen ions (protons). The electrons travel in the form of an electriccurrent that can be utilized before it returns to the cathode side ofthe fuel cell where oxygen has been introduced. At the same time, theprotons diffuse through the membrane to the cathode, where the hydrogenions are recombined and reacted with oxygen to produce water.

[0031] According to one PEM fuel cell construction, a PEM layer issandwiched between a pair of fluid transport layers (FTLs), such asdiffuse current collectors or gas diffusion layers for example. An anodeis situated between a first FTL and the membrane, and a cathode issituated between the membrane and a second FTL. In one configuration, aPEM layer is fabricated to include an anode catalyst coating on onesurface and a cathode catalyst coating on the other surface. Accordingto another configuration, the first and second FTLs are fabricated toinclude an anode and cathode catalyst coating, respectively. In yetanother configuration, an anode catalyst coating can be disposedpartially on the first FTL and partially on one surface of the PEM, anda cathode catalyst coating can be disposed partially on the second FTLand partially on the other surface of the PEM. The five layer constructdefined by the first FTL/anode/PEM/cathode/second FTL is referred to asa membrane electrode assembly (MEA).

[0032] The FTLs are typically fabricated from a carbon fiber paper ornon-woven material. Depending on the product construction, the FTLs canhave carbon particle coatings on one side. The FTLs, as discussed above,can be fabricated to include or exclude a catalyst coating. The FTLs,according to this product construction, are both porous and brittle. Acutting die apparatus consistent with the principles of the presentinvention is particularly well suited for accurately cutting thin, fuelcell layers, such as PEM layers and FTLs for example, during automatedfuel cell assembly.

[0033] Direct methanol fuel cells (DMFC) are similar to PEM cells inthat they both use a polymer membrane as the electrolyte. In a DMFC,however, the anode catalyst itself draws the hydrogen from liquidmethanol fuel, eliminating the need for a fuel reformer. DMFCs typicallyoperate at a temperature between 120-190 degrees F.

[0034] Molten carbonate fuel cells (MCFC) use a liquid solution oflithium, sodium and/or potassium carbonates, soaked in a matrix for anelectrolyte. MCFCs operate at about 1,200 degrees F. The high operatingtemperature is needed to achieve sufficient conductivity of theelectrolyte. Because of this high temperature, noble metal catalysts arenot required for the cell's electrochemical oxidation and reductionprocesses. MCFCs are typically operated on hydrogen, carbon monoxide,natural gas, propane, landfill gas, marine diesel, and simulated coalgasification products.

[0035] A solid oxide fuel cell (SOFC) typically employs a hard ceramicmaterial of solid zirconium oxide and a small amount of ytrria, insteadof a liquid electrolyte, allowing operating temperatures to reach 1,800degrees F.

[0036] In regenerative fuel cells, water is separated into hydrogen andoxygen by a solar-powered electrolyser. The hydrogen and oxygen are fedinto the regenerative fuel cell which generates electricity, heat, andwater. The water is then recirculated back to the solar-poweredelectrolyser and the process is repeated.

[0037] A protonic ceramic fuel cell (PCFC) employs a ceramic electrolytematerial that exhibits high protonic conductivity at elevatedtemperatures. PCFCs operate at about 1,300 degrees F. PCFCs can operateat high temperatures and electrochemically oxidize fossil fuels directlyto the anode. Gaseous molecules of the hydrocarbon fuel are absorbed onthe surface of the anode in the presence of water vapor, and hydrogenions are efficiently stripped off to be absorbed into the electrolyte,with carbon dioxide as the primary reaction product. These and otherfuel cell technologies can be constructed from material layers cut by acutting die apparatus in accordance with the present invention.

[0038] Turning now to FIGS. 2 and 3, there is illustrated an embodimentof a cutting die apparatus 40 according to an embodiment of the presentinvention. The cutting die apparatus 40 shown in FIGS. 2 and 3 includesa substantially planar die base 41. Provided on a top surface 42 of thedie base 41 is a cutting surface 44, which is shown protruding from thetop surface 42. Although FIGS. 2 and 3 show a single cutting surface 44,two or more cutting surfaces 44 can be provided on the top surface 42.

[0039] The cutting surface 44 is depicted as a continuous cutting edge.According to one configuration, the cutting surface has a substantiallysquare shape, as in the case of the cutting surface 44 shown in FIGS. 2and 3. The cutting surface 44 can also have a substantially rectangularshape. According to another configuration, the cutting surface can havea substantially oval or substantially circular shape. The shape of thecutting region 45 encompassed by the cutting surface 44 dictates thesize and shape of the resultant material layer cut by the cuttingsurface 44. The shape of the cutting surface 44 can be varied accordingto the intended shape of the material layers subject to cutting usingthe cutting die apparatus 40.

[0040] According to other embodiments, the cutting surface 44 may beconfigured to include a discontinuous cutting edge. The cutting surface44 may, for example, include one or more perforations, such as holes,breaks or other discontinuities. The cutting surface 44 may be definedby a number of loops of various shaped cutting edges. By way of furtherexample, the cutting surface 44 may include a single large rectangularshaped edge with several small circular or elliptical cutting edgesprovided within the large rectangular shaped edge. It will beappreciated that many variations of cutting surface configurations arecontemplated within the scope of the present invention.

[0041] The cutting surface 44 is preferably formed integral with the topsurface 42 of the cutting die apparatus 40. Alternatively, the cuttingsurface 44 can be separately formed and subsequently mounted to the topsurface 42 using known techniques. The height of the cutting surface 44relative to the back surface of the die base 41 preferably rangesbetween about 0.02 inches and about 0.08 inches.

[0042] In the configuration shown in FIGS. 2 and 3, the distance betweenopposing sides of the substantially square shaped continuous cuttingsurface 44 is about 6 inches. The length of the cutting die apparatus isabout 15 inches and the width is about 15 inches. According to thisconfiguration, the maximum thickness of the cutting apparatus 40, whichrepresents the cumulative thickness of the cutting die base 41 and thecutting surface 44, is about 0.04 inches. It is understood that theabove recited dimensions are provided only for purposes of illustration,and not of limitation.

[0043] The cutting die apparatus 40 also includes one or more bearers orstops 46. The bearers 46 are shown protruding from the top surface 42 ofthe cutting die apparatus 40. One or more alignment arrangements 48,such as alignment holes, are shown provided on one or more of thebearers 46. The alignment arrangement 48 provides for accurateregistration between the cutting die apparatus and an anvil surface whenemployed in a platen press. It is understood that an alignmentarrangement 48 other than alignment holes may be employed as is known inthe art. Further, it is understood that the alignment arrangement 48need not be situated at the bearer 46, but may instead be situatedelsewhere on the cutting die apparatus 40.

[0044] The bearer or bearers 46 are preferably formed integral with thetop surface 42 of the cutting die apparatus 40. Alternatively, thebearer or bearers 46 can be separately formed and subsequently mountedto the top surface 42. The height of each bearer 46 relative to the backsurface of the die base 41 preferably ranges between about 0.02 inchesand about 0.08 inches.

[0045] As is shown in the embodiment of FIGS. 2 and 3, the die base 41includes first, second, third, and fourth edges 61, 62, 63, 64, wherethe first and second edges 61, 62 respectively oppose the third andfourth edges 63, 64. The cutting surface 44 includes first, second,third, and fourth cutting edges 51, 52, 53, 54, where the first andsecond cutting edges 61, 62 respectively oppose the third and fourthcutting edges 63, 64. A first bearer 46 a is located between the firstedge 61 of the die base 41 and the first cutting edge 51, and a secondbearer 46 b is located between the third edge 63 of the die base 41 andthe third cutting edge 53 of the cuffing surface 44.

[0046] Alternatively, or in addition, a third bearer (not shown) can besituated between the second edge 62 of the die base 41 and the secondcutting edge 52, and a fourth bearer (not shown) can be situated betweenthe fourth edge 64 of the die base 41 and the fourth cutting edge 54 ofthe cutting surface 44. The location of the one or more bearers 46provided on the top surface 42 may be varied as needed or desired.

[0047] The cutting die apparatus, including cutting surface 44 and theone or more bearers 46, is preferably formed from a high strengthmaterial or metal, such as a hardened steel (e.g., spring steel). Thecutting surface 44 can be hardened to have a hardness greater than thatof the die base 41 and/or the bearers 46.

[0048] As was discussed previously, the height of each bearer 46relative to the back surface of the die base 41 is substantially equalto the height of the cutting surface 44. In one particular application,the height of the bearers 46 and cutting surface 44 ranges between about0.02 inches and about 0.08 inches, with about 0.04 inches representing aparticularly useful height.

[0049] Compliance can be built into the cutting die apparatus 40 byinclusion of a thin compliant material situated between the back surfaceof the die base 41 and a platen press surface. One, two, or more layersof the compliant material can be employed. The compliant material ispreferably formed from a polymeric material, such as polyethylene orpolypropylene. Each layer of the compliant material preferably has athickness ranging between about 0.002 inches and about 0.008 inches.

[0050] Referring now to FIG. 4, there is illustrated an embodiment of aplaten press 50 which incorporates a cutting die apparatus 40 of thepresent invention. Because the cutting die apparatus 40 of the presentinvention incorporates one or more bearers or stops 46, the need forexpensive external press stroke stops provided on the platen press isobviated, as is the need for careful adjustment of such stops by askilled machinist after each die change.

[0051] The platen press 50 shown in FIG. 4 includes a base plate 52 towhich a number of supports 60 are attached. Also connected to thesupports 60 is a top plate 54. The base and top plates 52, 54 aretypically stationary structures. A moveable plate 56 slidably engagesthe supports 60 and is movable relative to the base and top plates 52,54. Movement of the moveable plate 56 is controlled by an actuator 58shown mounted to the top plate 54. The actuator 58 is typically apneumatic or hydraulic actuator which can be controlled to move themoveable plate 56 toward and away from the base plate 52. The actuator58 can be controlled by an appropriate control device.

[0052] The base plate 54 of the platen press 50 includes an anvilsurface 65. The anvil surface 65, as discussed previously, is formedfrom a hard material, such as hardened metal. In applications in whichvery thin material layers are to be cut, it is desirable to include oneor more compliant backers 49 between the back side of the cutting dieapparatus 40 and the adjacent support surface of the moveable plate 56.In one application, two compliant backers 49 each having a thicknessranging between about 0.004 inches and about 0.006 inches can besituated between the back side of the cutting die apparatus 40 and theadjacent support surface of the moveable plate 56.

[0053] In operation, a thin layer of material to be cut is appropriatelyplaced on the anvil surface 65 of the base plate 52. A control signal,which may be a hydraulic, pneumatic or electrical signal, iscommunicated to the actuator 58. In response to the control signal, theactuator 58 moves the moveable plate 56 and cutting die apparatus 40toward the anvil surface 65. As the cutting die apparatus 40 contactsthe layer of material resting or otherwise being held in place on theanvil surface 65, such as by use of a vacuum, the force generated by theactuator 58 causes the cutting surface 44 of the cutting die apparatus40 to penetrate the layer of material.

[0054] The moveable plate 56 continues to move toward the anvil surface65 under the force generated by the actuator 58 until the bearer(s) 46contact the anvil surface 65. Because the bearer(s) 46 are substantiallythe same height as the cutting surface 44, the cutting surface 44 makesslight contact with the anvil surface 65 to complete the cut to thelayer of material, but is prevented from further movement toward theanvil surface 65 by contact between the bearer(s) 46 contact the anvilsurface 65. As such, damage to the cutting surface 44 is prevented.

[0055] After cutting the layer of material, a control signalcommunicated to the actuator 58 causes the actuator 58 to retract themoveable plate 56 to a non-engaged position relative to the anvilsurface 65. The cut layer of material can then be removed from the anvilsurface 65, either automatically or manually. The above describedcutting process is repeated for subsequent material layers.

[0056] The foregoing description of the various embodiments of theinvention has been presented for the purposes of illustration anddescription. It is not intended to be exhaustive or to limit theinvention to the precise form disclosed. Many modifications andvariations are possible in light of the above teaching. It is intendedthat the scope of the invention be limited not by this detaileddescription, but rather by the claims appended hereto.

What is claimed is:
 1. A cutting apparatus for use with a platen diestation for cutting relatively thin planar material layers, comprising:a die comprising a substantially planar first surface and asubstantially planar second surface; a cutting surface protruding fromthe first surface of the die; and at least one bearer surface protrudingfrom the first surface of the die, a height of the bearer surfacesubstantially equal to a height of the cutting surface, such that thebearer surface prevents damage to the cutting surface when the cuttingsurface and bearer surface are moved to contact an anvil surface of theplaten die station.
 2. The apparatus of claim 1, wherein one bearersurface protrudes from the first surface of the die.
 3. The apparatus ofclaim 1, wherein a first bearer surface is located proximate a firstedge of the cutting surface and a second bearer surface is locatedproximate a second edge of the cutting surface.
 4. The apparatus ofclaim 1, wherein the die comprises first, second, third, and fourthedges, the first and second edges respectively opposing the third andfourth edges of the die, a first bearer surface is located proximate thefirst edge of the die and a second bearer surface is located proximatethe third edge of the die.
 5. The apparatus of claim 4, wherein a thirdbearer surface is located proximate the third edge of the die and afourth bearer surface is located proximate the fourth edge of the die.6. The apparatus of claim 1, wherein the cutting surface comprises acontinuous cutting edge.
 7. The apparatus of claim 1, wherein thecutting surface comprises a discontinuous cutting edges.
 8. Theapparatus of claim 1, wherein the cutting surface has a substantiallysquare or substantially rectangular shape.
 9. The apparatus of claim 1,wherein the cutting surface has a substantially oval or substantiallycircular shape.
 10. The apparatus of claim 1, wherein the cuttingsurface comprises an outer cutting edge and one or more inner cuttingedges respectively situated within the outer cutting edge.
 11. Theapparatus of claim 1, wherein the cutting surface is integral with thedie.
 12. The apparatus of claim 1, wherein the die, the cutting surface,and the at least one bearer surface are respectively formed from a highstrength metal.
 13. The apparatus of claim 1, wherein the at least onebearer surface comprises an alignment arrangement, the alignmentarrangement located on the at least one bearer surface to register withan alignment arrangement of the platen die station.
 14. The apparatus ofclaim 13, wherein the alignment arrangement comprises at least onealignment hole.
 15. The apparatus of claim 1, wherein the height of thebearer and cutting surfaces ranges between about 0.02 inches and about0.08 inches, respectively.
 16. The apparatus of claim 1, furthercomprising one or more layers of a compliant material in contact withthe second surface of the die.
 17. The apparatus of claim 16, whereinthe compliant material comprises a polymeric material.
 18. The apparatusof claim 16, wherein the compliant material comprises polyethylene orpolypropylene.
 19. The apparatus of claim 16, wherein each compliantmaterial layer has a thickness ranging between about 0.002 inches andabout 0.008 inches.
 20. A platen die assembly for cutting relativelythin planar material layers, comprising: a first plate and a secondplate, the second plate comprising an anvil surface, the first plate andsecond plate arranged to permit relative movement therebetween; a diecomprising a substantially planar first surface and a substantiallyplanar second surface, the second surface of the die affixed to thefirst plate; a cutting surface protruding from the first surface of thedie; at least one bearer surface protruding from the first surface ofthe die, a height of the bearer surface substantially equal to a heightof the cutting surface; and an actuator that effects contact between thefirst and second plates, the bearer surface preventing damage to thecutting surface when the cutting surface and bearer surface are moved tocontact the anvil surface of the second plate under pressure.
 21. Theassembly of claim 20, wherein one bearer surface protrudes from thefirst surface of the die.
 22. The assembly of claim 20, wherein a firstbearer surface is located proximate a first edge of the cutting surfaceand a second bearer surface is located proximate a second edge of thecutting surface.
 23. The assembly of claim 20, wherein the die comprisesfirst, second, third, and fourth edges, the first and second edgesrespectively opposing the third and fourth edges of the die, and a firstbearer surface is located proximate the first edge of the die and asecond bearer surface is located proximate the third edge of the die.24. The assembly of claim 23, wherein a third bearer surface is locatedproximate the third edge of the die and a fourth bearer surface islocated proximate the fourth edge of the die.
 25. The assembly of claim20, wherein the cutting surface comprises a continuous cutting edge. 26.The assembly of claim 20, wherein the cutting surface comprises adiscontinuous cutting edges.
 27. The assembly of claim 20, wherein thecutting surface has a substantially square or substantially rectangularshape.
 28. The assembly of claim 20, wherein the cutting surface has asubstantially oval or substantially circular shape.
 29. The assembly ofclaim 20, wherein the cutting surface comprises an outer cutting edgeand one or more inner cutting edges respectively situated within theouter cutting edge.
 30. The assembly of claim 20, wherein the cuttingsurface is integral with the die.
 31. The assembly of claim 20, whereinthe die, the cutting surface, and the at least one bearer surface arerespectively formed from a hardened metal.
 32. The assembly of claim 20,wherein the at least one bearer surface comprises an alignmentarrangement, the alignment arrangement located on the at least onebearer surface located to register with an alignment arrangement of thesecond plate.
 33. The assembly of claim 20, wherein the height of thebearer and cutting surfaces ranges between about 0.02 inches and about0.08 inches, respectively.
 34. The assembly of claim 20, furthercomprising one or more layers of a compliant material situated betweenthe second surface of the die and the first plate.
 35. The assembly ofclaim 34, wherein the compliant material comprises a polymeric material.36. The assembly of claim 34, wherein the compliant material comprisespolyethylene or polypropylene.
 37. The assembly of claim 34, whereineach of the compliant material layers has a thickness ranging betweenabout 0.002 inches and about 0.008 inches.